Synthesis of Potassium trioxalatochromate(III)

2.3 g of potassium oxalate monohydrate and 5.5 g of oxalic acid dihydrate are dissolved in 80 mL of water. A slow addition of 1.9 g of potassium dichromate is started with vigorous stirring, the solution is then evaporated down to 1/10th of the volume with a hot plate. The product crystallizes out in a trihydrated form.